LAKE BUENA VISTA, Fla. -- At Walt Disney World's Animal Kingdom, head veterinarian Mark Stetter demonstrates the 5-foot contraception tool for a procedure that he hopes will help control Africa's elephant population: vasectomies.

The theme park's plan is the latest attempt to deal with what African officials say is overpopulation, although conservationists dispute that. While those who live far from elephants may think they are endangered, thousands of them have been killed in Africa because of concerns that they had overwhelmed certain areas.

Eating up to 600 pounds of vegetation a day, they can destroy their environment if too many are in a confined space. In South Africa's Kruger National Park alone, more than 16,000 were culled from 1966 to 1994, when a moratorium was enacted due to public pressure. Some parks like Kruger are still lobbying for that option.

"I think that obviously everybody would agree that culling has caused a lot of social issues with the elephants," Stetter said. "Part of our hope is that there will be less culling in the years ahead if we are able to use this tool."

But some African wildlife experts and advocates say the vasectomies plan is ill-conceived, blaming the problem instead on elephants in parks being confined to small areas that don't resemble the natural ecosystem.

"When it comes to conservation, we excuse ourselves and deal with the symptoms instead of the causes," said Rudi van Aarde, director of the Conservation Ecology Research Unit at the University of Pretoria in South Africa. He advocates linking parks together to create larger ecosystems that will naturally limit elephant populations.

The vasectomies plan was devised to help solve problems with culling and transplanting elephants, which can adversely affect the animals' families.

Experts say younger elephants who grow up without discipline from their dominant fathers can suffer developmentally. An increase in elephant attacks on humans has been seen in parts of Africa where they live side-by-side.

With a three-year, $60,000 grant from Disney's Conservation Fund, Stetter developed his procedure with help from an animal anesthesiology expert from the San Diego Zoo and a laparoscopic horse surgeon from Colorado State University. Stetter trained several African vets in the procedure this summer.

The two biggest challenges: elephants are the size of semi-trucks, and their testicles _ the size of a "respectable cantaloupe," Stetter said _ are behind 2 inches of skin, a foot of muscle and 4 inches of fat.

"What we want to do is get to the middle of something that's in that semi-truck, and we want to do it without emptying out everything that's in the truck," Stetter explains.

Using the tools doctors use for arthroscopic knee surgeries on humans _ a laparoscope and a video monitor _ Stetter can perform what he says is a two-hour procedure to sterilize male elephants without disrupting their important testosterone production.

The elephant must first be shot from a helicopter with an anesthesia dart, guided to an open area, and propped up by a crane truck so that he can stand while sleeping.

Stetter said field tests, as recently as July in South Africa, have revealed no postoperative complications for the elephants.

But Jason Bell, southern Africa director for the International Fund for Animal Welfare, wrote in an e-mail he is concerned about the practicality and safety of vasectomies.

Humans have chosen to place elephants in confined areas for a number of reasons.

"People have put elephants on a pedestal for a long time, more so in Europe and America than Africa because you have to remember that livelihoods are affected here," van Aarde said. "They have become a symbol of conservation success. If you fail to take care of elephants you fail in conservation, therefore politically it has become extremely important."

Stetter realized when he started the program that he was subjecting himself to heated debate.

"One of the biggest learning curves that I've been on is that there are many different groups over there with different agendas so there is no clear-cut answer," he said.